The present invention relates to an electrode substrate as is known from DE 20 2009 005 751 U1. The present invention also relates to a flat optoelectronic device, particularly an organic optoelectronic device in which such a flat electrode substrate is used, and a method for manufacturing an electrode substrate.
An electrode substrate known from the prior art is known from WO 2010/051976 A1, which is held by the applicant. In that document, it was disclosed for the first time that, for optoelectronic devices such as solar cells, light-emitting devices or the like, transparent electrode surfaces such as were implemented in traditionally known manner using electrically conductive oxide layers (TCO=transparent conductive oxides) could advantageously be replaced with easily manufacturable fabric surfaces having reproducible properties and favourable electrical conductivity. In particular, the prior art to which reference was made as representative of the species enabled the flexible capability of implementing the electrical conductivity properties desired for each individual case using a fabric of electrically conductive and non-conductive fibres, and the capability of avoiding undesirable, resistance-related voltage drops such as occurred for example in large area TCO elements (when ITO is used, for example), and at the same time of using the flexible properties of a fabric additionally and advantageously, although opportunities for use were traditionally limited by the typically brittle TCO material.
However, it was found during further developments of fabric-based electrode substrates for optoelectronic devices that a substructure known precisely from WO 2010/051976 has a comparatively high surface roughness due to the combination of fabric and the polymer coating that (partially) soaks the fabric while not itself being conductive, which surface roughness has proven to be unfavourable for such organic optoelectronic devices (such as organic solar cells); thus for example (surface roughness induced) inhomogeneities have an unfavourable effect on the optoelectronic properties desired in a given case.